Alittle bit of nipping is ok, thats normal. Chasing is normal too as long as its not fighting and grunting. They will have some dominance issues to work out at first.
One thing I do to encourage one to groom the other is rub ones butt while his head is near the other. So ifMurphy and Ella are facing one another you can try rubbingMurphy's butt, which might encourage him to lick her.
Ive put a tiny amt ofpeanut butter on one bunny's head before and that worked. a little banana (or pumpkin or baby food) would probably work as well.
Keep usposted!